Air Force investigators believe a specialized flight suit could be partially responsible for some pilots experiencing a lack of oxygen while flying the F-22 fighter jet, according to a report by Air Force investigators.

Investigators are focusing on part of the suit, called the "Combat Edge," which hampers breathing and causes oxygen loss when combined with a physiological condition that collapses air sacs in the lungs, according to details of the report that were shared with Security Clearance.

The findings are expected to be part of the first monthly update by Air Force investigators to Secretary of Defense Leon Panetta to be delivered later this week or early next week, according to sources familiar with the investigation.

Last month, Panetta ordered the updates on the investigation after the Air Force could not identify the cause of the continued issues with pilots complaining about coming close to passing out while flying the plane, which the service called "hypoxia-like symptoms."

Combat Edge is a vest-like garment that expands and contracts on a pilot's torso to fight the effects of severe G-forces experienced while flying the F-22. The problem being looked at is that the garment may restrict the pilots' breathing beyond what is intended, according to sources familiar with the report.

Another possible problem for pilots, the report is expected to say, is a condition called acceleration atelectasis, which causes a pilot's lungs to not effectively deliver oxygen to the bloodstream. The condition for F-22 pilots is caused when extreme gravity and breathing almost pure oxygen in the F-22 cockpit partially collapse air sacs in the lungs, according to the sources.

Acceleration atelectasis causes a heavy cough, which F-22 pilots have called the "Raptor cough" after the nickname of the fighter, "Raptor."

Pilots have complained about the cough in connection with the hypoxia-like conditions as they fly the F-22, the most technologically advanced plane in history, often at altitudes much higher than regular aircraft fly. The pilots also perform maneuvers that put their bodies through extreme conditions.

In an e-mail response to questions by Security Clearance, Air Force spokesman Lt. Col. John Dorrian said, "Recent testing has identified some vulnerability and reliability issues in the upper pressure garment worn by F-22 pilots. Air Combat Command has directed pilots to remove the upper pressure garment during routine flight operations, and Air Force officials are developing a fix to overcome the identified issues."

The findings in the update report to be given to Panetta are not final, according to the sources. Air Force officials say investigators are narrowing down the cause of the problem, which has intermittently plagued the aircraft since 2008.The problem compounded in September 2011 as more pilots complained of experiencing the symptoms.

The fleet was grounded in May 2011 so the service could check the hypoxia reports, but the order was lifted in September under a "return to fly" plan, with equipment modifications and new rules including daily inspections of the life-support systems.

Investigators initially pointed to an onboard oxygen generating system that pilots used to breathe as a possible cause.

Lockheed Martin, the maker of the jet, was given a $19 million contract to install a backup oxygen system in the F-22 last week.

Last month, Panetta mandated that all F-22 flights "remain within the proximity of potential landing locations" to ensure the ability to recover and land should a pilot run into "unanticipated physiological conditions."

Scott Rawlings / Thanks Will. It was one of those days when everything comes tetgoher. Everyone had a great time. Some flew for nearly three hours. Eleven people flew and enjoyed this fantastic site with only one bent downtube. (Thanks for filming Cols landing and the subsequent interview. I'll get mileage out of that for some time.) You being there and filming it just made it even better. Hope we can all do it again very soon.Scott Rawlings.

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The "oxygen problem" story could be likely cover for a problem they do not want to expose – caused by the warfare electronics.... and if they did talk about it, the discussion could bring up dangers in civilian exposure to similar "fields" – electromagnetic, etc.

sounds a lot like what happens when breathing Nitrox (oxygen enriched air) under pressure. You can't go below 130 ft since oxygen is toxic at those pressures...I'd think that at multiple G forces breathing pure O2 would have a similar effect....

time to consider other manufacture of warplanes , american suppliers cost too much and produce substandard results . they also play cya to the tune of millions of dollars after they screw up . seems that the g forces experienced are nearly at the limits of human tolerance too . it may be time to consider either uav use and or liquid immersion environments for pilots .

Hi Erin,I sent you an email yesterday but wasn't sure if you reecived it. I just had a baby last week and would be interested in coming in if you are still needing newborns. He is 7 days old today.Thank you so much,Danielle

At $412,000,000 each – I'd recommend it's time to weld the seats into the plane. There was a time when the jet was disposable – "we can build more – we can't replace you". I'd suggest that it's easier to replace the pilot today than a $412,000,000 fighter. Everyone else seems to manage without the ACES II – maybe it's time for the fighter guys to figure out how to save their jet or ride it in?

Maybe we should ask the Chinese how they solved the problem on their F-22 design they borrowed from us. I grew up in the 1960's when we made things in this country and didn't outsource anything. Today about the only things that are still "Made In America" are babies and half of them are Chinese and Mexican babies.

Ed Sizemore Posted on How does the fact the Heidi's blog is hosted by Publisher's Weekly afecft what your saying? Given that Publisher's Weekly is a news organization, this seems to blur the lines between private webpage and corporate web columnist significantly. If Heidi is writting The Beat as a Publisher's Weekly employee, then the argument changes significantly.

This situation is easy to test: simply fly the Raptor within the normal test envelope of, say an F-16, for several months and see if the hypoxic symptoms persist. If so, then the typical F-22 stresses on human anotomy are not to blaim, but some other substance that the pilots are exposed to.

Part of the problem is that the investigation is being done by the AF and the contractors, the people who have the most reason to play CYA. Call in an impartial outfit like the NTSB and you might get results

Why on earth are they using pure O2 anyway? Everyone else who breathes SCBA gases NEVER use pure O2, for good reason (not least of which is fire safety...look at what happened to NASA Apollo 1). I don't see why they don't just add in a blend of nitrogen. Ever heard of Nitrox? And I agree with a some of these other posters here, it sounds to me like either the composite structure and/or nanostructured RF absorbing paint might at least partially be to blame, it's at least worth checking.

They will pass us up.thers will work better. there use to be a time when people of the usa took pride in the fact that we had the tallest bulding , longest brige , fastest plane ,fastest train and so on.We dont care any more and next thing we get a ass handed to us.

June 14, 2012 at 2:50 am |

Real McCoy

TOP CAT, if we wanted the opinion of primitive communists that had to copy everything in their whole country from outside their borders we'll let you know. Go eat some gutter soup or melanine milk or whatever it is you eat in your commie hell hole.

June 14, 2012 at 3:27 am |

Real McCoy

Despite what your government tells you, your country invented NOTHING of importance ever since you were communist led. So go back to begging us for our tech or stealing it, because you are worthless.

June 14, 2012 at 3:28 am |

Zachary

Ugh... I hate all these arguments about "Such and Such country has to copy us" and "This thing is a clone of our original" that pop up so often when Military Aviation is the issue. Simple fact is, if you have the most advanced aircraft in the world that fills one of the most vital roles in warfare, everybody else will have to play catch up just to remain a threat. Aerodynamics and the interaction between Electromagnetic Energy and physical matter doesn't magically change from one part of the world to the next. So if we design an aircraft to be as aerodynamically and detection avoidance efficient as physically possible, then any country or company with the same goals in mind for their own designs will undoubtedly arrive at a similar shape. Variation in design will come as a result in variation in priority. The F-22 is much more aerodynamically designed because the priority was stealth. The PAK-FA sacrifices some of that stealth in favor of more favorable aspects for maneuverability. The Chinese are simply a full generation behind in their own domestic development (To which they freely admit) and so their design's likely going to be a more Jack of all Trades in balancing speed, stealth and maneuverability due to their lack of research in Radar Cross-section oriented design's effect on Aerodynamics.

June 14, 2012 at 4:30 am |

Craig

So, the other information aside, LM has been given a multi-million dollar contract to add new stuff to the plane, because the old stuff which they built doesn't work. Somebody...anybody...tell me why this an acceptable way to operate. I'll check back from time to time, but I doubt business not selling to the government could do business this way. Anywhere else, you'd be told "...fix it so it works, or you don't get paid for anything...and we're not paying more to get you to do it right."

That's because you're simple minded and like so many others on here, want to believe there's always a 'simple fix'. When you push the bounds of technology these are the kinds of problems you encounter. You fix them, and move on. Painful? Yes. Expensive? Most of the time? Worth it? To rule the skies in peacetime and conflict? No question.

This plane is a 20 year old design. Combat ready, right? Even the concept is obsolete. It goes on swallowing money.

June 14, 2012 at 1:57 am |

Mark

SHeesh, why don't you lick the marketing brochure too. No one is arguing that the cutting edge bears risks, nor are they suggesting "simple fixes"....the fact remains they built it, they designed it, and they should fix it – or we end up footing the bill for an overpriced paper weight. the Raptor has had its share of problems, many allied nations don't even want to buy it, but trying to deflect by insulting others is just juvenile – and most of us can see through the spin.

June 14, 2012 at 2:29 am |

Trevor

Glenn- Its obvious you've never seen the Raptor perform at various exercises around the states...I've been to Red Flag on numerous occassions and the Raptors OWN the Aggressors everytime they fly. The Aggressors at Nellis are the most higly trained pilots in the world and fly both the F-16 (Blk 30) and MSIP 15Cs that are no "slouches". The only thing that held back the Raptors for dominating the entire vul time (ie: time from Blue Air "push" [ingress] to Blue Air "safe" [egress]) was running out of fuel and missles. Finally, the Raptors also for OPSEC reasons don't operate in the "wartime mode" during these exercises or it would be even uglier for the Aggressor pilots. Obsolete? The Raptor has a significant advantage over any Su-30/35, Gripen or Rafale in service and a healthy advandage over the Typhoon. Again, obsolete? Not even close.

June 14, 2012 at 4:22 am |

Craig

I didn't say there was a simple fix, nor am I particularly simple-minded. What I said was that the company that built the planes claimed they supplied a functional aircraft that met the specifications supplied by DoD. They got paid for doing that. Now, it appears, they didn't. Assuming they are responsible for their actions, which, unfortunately, most big companies never are, they should stand up and fix the thing...without additional payment.

Now, if that's your definition of "simple minded" then I suspect you get taken a lot. You buy a car, it doesn't work, so you take it back and offer to pay more...to the same outfit...to get the same car but actually functional? Nope. You wouldn't and I wouldn't either. Why does the government? And, for the record, providing breathable air to a pilot in a high-performance aircraft isn't a new concept. It's been around since...well...before WWII. While the various methods might have changed, the idea is still pretty much the same. The pilot needs oxygen to function, and there isn't enough in the ambient air at higher elevations, so that means you create some system to provide it. Heck, we learned about that when we were taught HALO jumping techniques, and that was clear back in the 60's.

So, if you think demanding that a company produce a usable product is "simple minded" then I guess I'd agree. If, on the other hand, you think a company should be allowed to produce a non-functional product, get paid, and then demand or expect to get paid more to fix the non-functional product so it actually does what they claimed it did, I'd say you should get a job in procurement at DoD, because no other company or individual is going to work that way. I reminds me of the last time I had to renew my passport. I went down, paid the fee, and they lost it. When I showed up with my receipts and cancelled checks, they told me that if I submitted another application...with another fee, I'd get my passport. I declined, and told them they'd been paid for the work, and they were obligated to either refund the original fee or produce what they'd been paid to produce. They were...dumbstruck, and remained that way until my Senator's office called them and explained things further. Oddly enough, they then immediately located my original application and managed to process it. We get the government we deserve, and if we allow this, then...we deserve it.

June 14, 2012 at 6:59 am |

Herby Sagues

I see your point, but these are no car salesmen. If you are asked to build a cutting edge, never built before, extremely expensive thing, you, as a businessman, have two possible approaches. Either pad the cost up massively up-front, so you can cover any unforeseen incremental cost (which WILL be there, you just don't konw how much it will be) or you can put a contract that says that, once you deliver the plans for the product and they are approved, you are not responsible for the cost of design changes, even if due to errors in design.
It would be nice if someone made an offer that didn't include either of those, but no sensible businessperson would do it. If they did, they would be out of business very soon, and future projects would be in the hand of those that planned better.
So no, this is not evil, nor unfair, nor abusive. It is the only way it can be in cutting edge, uncharted territory business, which is where the US Air Force wants to be.

Craig: because that's how corporate welfare works. The entire DoD acquisition system is not just dysfunctional, it is guaranteed to result in "food chain" projects that drag on forever. There is no incentive (yet) for contractors to deliver weapon systems on budget, on time, etc. because they have MASSIVE infrastrcuture and labor cost structures to support. all of this will end soon enough, though, because the MIC and financial services parasites have bled the host (US Govt) dry, and our resulting Greece-like collapse is coming soon.

This is just another distraction from the real truth. The composite materials that make up the plane are toxic. If the issue was the flight suits all the cases of ground crew getting sick would not be present as they don't wear flight suits.

It is a major problem, but in the epelxmas that you have given it takes no time at all for them to respond to just acknowledge they have received your email / enquiry and get back to it as soon as poss, and if they haven't had a chance to get back to you properly for a while to just send an update to you.

September 11, 2012 at 12:42 am |

Juxsaposs

The OBOGS Is out sourced to England by the same Corporation that KILLED 5k residence in India(about 30 yr ago)then Bought a new name and cares only about PROFIT. The CEO of this Corporation spends as much time with Barak as Michelle does.

Yes, their products Look very good on Paper, but from personal experience do not handle deviations from perfection at all. If only We lived in a perfect World!

I say "look at Obamas Buddy for Both the problem and the Cover-UP"!!!!

I was interested to read that some of the composite materials that are used in the construction of the F-22 (particularly those related to it's reduced radar cross signature) could be what's contributing to the issue. Some have known toxic qualities, and once heated, maybe they give off toxic fumes or something. this would account for both the ground crew and the pilots' health issues. I think i read it on wikipedia, but it was cited, and it makes perfect sense.

Right, these planes are not heated by exhaust gasses like a passenger plane. All oxygen and habitacle gases are packed inside tubes. Since interior cabin is WAY higher than exterior cabin during any flight at considerable speed If there was any connection between the exterior and the interior air would be leaking out, not in. So no, it is almost impossible that the pollutants (if there are any) are coming from the outside. That could explain the dizziness some of the mechanics are experiencing, but not that of the pilots.

June 14, 2012 at 12:42 am |

Arm chair engineer

Possibly transdermal but I'm sure that theory has been tested.

To several of the negative complainers out there: I want the defense contactors to be accountable as much as possible on production and support costs as the next guy but at the end of the day I would rather be the Top dog in this global tactical rat race than being a soft target for the bad guys. If we don't stay ahead of the game they will be on us like pitbulls.

An F22 can produce much higher Gs than an F-15 or an F16, so these are modified suits with higher operational pressures. Also, these suits have elctronic controls, and the programming might be wrong for the aircraft's patterns.

On a regular plane, I would say "to evade missiles". But since this plane has the radar cross section of a small bullet, it is probably over-designing the thing.
Now, if we talk about fighting last century's fith, the whole plane is a waste. Why spend hundreds of millions of dollars building MANNED planes that are less agile, more vulnerable and more dangerous than unmanned planes that could cost a fraction of that money?
They could build a much smaller, equally powerful, remotely controlled manned plane for 10% of what these things cost.
I guess it's a direct result of pilots making the decission. They are the only ones qualified for making the decision and at the same time they are the ones that are less impartial at doing it.

To be completely honest with you, there really isn't a need for sustained g's above 5. I can't speak for the F-22 (I would imagine that it would still apply) but the F-18E/F models perform great in all situations with 5 g's or less. Legacy/Super Hornets have g limiters at 7.5 g's and I RARELY get close to that level. However the limiter can be turned off and up to 9 sustained g's are possible. But above 6 or 6.5 g's it gets really uncomfortable so most pilots, in the Navy at least, don't pull those kinds of g's.

"HornetDriver" – I will give you this, as it has been some time (5 years) since I have worked a fighter with integrated avionics....please explain this "g-limiter" you speak of. It is interesting to me, as I have been on the maintenance end of aircraft that have over-g'd. I only ask because I would like to know the manufacturer of this avionic component...the g-limiter.

July 8, 2012 at 5:07 am |

The Left Wing

Are the G forces experienced in flying an F-22 substantially greater than those experienced in an F-16 or F-15? Is a different flight suit needed?

Pilots have been subjected to the same forces in other jets such as the F-16 and so forth. What is different about the Raptor? Only the way the oxygen is produced, as far as I've heard. I remember seeing pilots in 'g-suits' back in the 50's

Grege, if you've ever seen an F-22 flight demonstration, you'd know that these pilots are pulling way more G's than the F-16 pilots. The vectored thrust simply puts a strain on these guys like never seen before.

Why do people on the internet feel to the need to make up their own conclusions when their expertise in the field is probably as much as watching an episode of Modern Marvels on the History channel about the subject.

Great point! But... Aren't you coming up with your own conclusion about the experience levels of people in this comment section? 😀

June 13, 2012 at 11:16 pm |

Colin

Don't take the internet so seriously friend.

June 13, 2012 at 11:19 pm |

Arm chair engineer

Because it keeps you thinking and it's entertaining! :o)
That's what makes us Americans. We are always stirring things around to get to the next level or figure things out.

June 14, 2012 at 3:30 am |

Fred Evil

Not an issue with oxygen pressure hoss, under G forces, your blood behaves as if it were much heavier as well as your arms/legs, meaning it drains to your feet, and your heart has a very hard time pumping it into your head, which then means less oxygen is carried to your brain by the substantially reduced flow of blood.
G-Suits and their ilk usually squeeze your legs and/or arms like a balloon, so that the blood cannot pool there, and your heart has an easier time getting it to your brain.

"airhead – Its related to air pressure rebounding between the ferndock and simulet."

Can't be; the ferndocks were redesigned (at a cost of 40 million), and the simulets were all individually tested and replaced (for another 57 million). My bet is it's the carburetor belts slipping.

June 14, 2012 at 2:14 am |

Arm chair engineer

No it's the muffler bearings in conjunction with the flimminflanger valve.

June 14, 2012 at 3:40 am |

Rich

"How does that address the similar complaints of Raptor cough made by ground crews working on the aircraft?"

From the article:

"The Combat Edge problem does not explain why some mechanics have also suffered from hypoxia while working on the planes on the ground."

So... it doesn't. But chasing this wild goose makes them feel like they're making progress. I mean, I suppose it *could* be multiple causes with the same symptoms – but even if they're right about the Combat Edge being the problem, it doesn't fully address the issue.

Why does it have to be the same cause?
Ground crews are exposed to the exterior materials. Pilots are not (and, given operational pressure at the cabin, air from the exterior can't get in once the plane is flying). So whatever the cause, it is most likely unrelated. Two separate design defects.

I have to agree. That's why I think that remote operated combat fighters are the way to go like another guy posted.
Major increase in capability, smaller, and should have lower costs. Don't forget you still have to have a pilot on the ground and support systems to fly it.

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CNN's Security Clearance examines national and global security, terrorism and intelligence, as well as the economic, military, political and diplomatic effects of it around the globe, with contributions from CNN's national security team in Washington and CNN journalists around the world.